Date: Wed, 12 May 93 05:00:05 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #554 To: Space Digest Readers Precedence: bulk Space Digest Wed, 12 May 93 Volume 16 : Issue 554 Today's Topics: "365 days of the Shuttle flights" ASTRONAUTS---WHAT DOES WEIGHTLESSNESS FEEL Boom! Whoosh...... (3 msgs) FAQ and Sky hooks.. HST Servicing Mission landing at Edwards vs. the Cape Life on Mars. (3 msgs) Location Devices for RVs, also SARSATs Mars Observer Update - 05/10/93 Neil Armstrong's first words (the real ones) Space Advertising Space Advertising and Visual Acuity Vandalizing the Sky (2 msgs) Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: 11 May 1993 00:00:55 GMT From: Pawel Moskalik Subject: "365 days of the Shuttle flights" Newsgroups: sci.space >> Why did you leave out the Progress freighters? They're an integral part >> of the Mir program and of Soviet/Russian manned spaceflight in general. -- >> SVR4 resembles a high-speed collision | Henry Spencer @ U of Toronto Zoology >> between SVR3 and SunOS. - Dick Dunn | henry@zoo.toronto.edu utzoo!henry True. I just wanted to compare one manned spacecraft (shuttle) with another manned spacecraft (Soyuz). Because Russians separate manned and cargo operations and USA do not, it will be always a matter of choise how to make such comparison. For example, if somebody wants to compare the cargo delivered to orbit, then shuttle should be measured against Tytan, Proton, Soyuz (the launcher) etc, rather then Progress. Between 1981 and now: Progress missions launched: 49 Mission sucess rate: ?? (100 percent ?) rendezvouz operations: 50 ? cargo delivered: ?? (150 tons ?) cargo returned: ?? (1 ton ?) To be complete, there have been also 6 large modules launched to the Salut 7 and MIR stations (Cosmos-1227, Cosmos-1433, Cosmos-1686, Kvant, Kvant-2, Kristall). If i remember correctly, two first of them returned to Earth big capsules. Pawel Moskalik ------------------------------ Date: Mon, 10 May 1993 22:12:21 GMT From: kjenks@gothamcity.jsc.nasa.gov Subject: ASTRONAUTS---WHAT DOES WEIGHTLESSNESS FEEL Newsgroups: sci.space PATE, DENNIS WAYNE (dwp7692@rigel.tamu.edu) wrote: : : Two years ago a took a tour of the Johnson Space Center with a group of : fellow Human Factors Engineering graduate students. Our guide was a : manager in the Man Systems Dept. and a friend of our prof. While : showing us the mockup of space station Freedom (the pre-Clinton : design), he pointed out a new project one of the groups was working : on. They had observed that some of the astronauts prone to developing : motion sickness were not as succeptable to it once they had returned : from a mission. The positive side-effect apparently last for a couple : of weeks, depending on the individual. They hoped a reversal of the : situation might also work (i.e. Get them motion sick on the ground, let : them recover, and then boost them into space). To accomplish this, : they were constructing some type of miniature roller-coaster (that's : how our guide describe the device). : : I don't know if the device worked, or if it was ever actually completed : and used. If anyone knows anything about it, please post. I was a test subject in that thing. They're calling it the Pre-flight Adaptation Trainer (PAT). Dr. Harm here at MSC (oops, I mean JSC) seems to be in charge. -- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office kjenks@gothamcity.jsc.nasa.gov (713) 483-4368 "A scientist can discover a new star, but he cannot make one. He would have to ask an engineer to do that." -- Gordon L. Glegg, American Engineer, 1969 ------------------------------ Date: 10 May 1993 16:14:41 -0400 From: Pat Subject: Boom! Whoosh...... Newsgroups: sci.space In article <1993May10.134819.8227@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: > >In article <37860@scicom.AlphaCDC.COM> wats@scicom.AlphaCDC.COM (Bruce Watson) writes: >The more serious problem would be finding the hanger for painting >on the logos before launch. Echo was inflated in a blimp hanger, >but a one mile high hanger might be harder to find. :-) I would imagine use integral logos. Continously form the balloon material, with variations in color or reflectivity manufactured into the material. no-one wants to paint that much:-) pat ------------------------------ Date: Mon, 10 May 1993 22:33:20 GMT From: "Simon E. Booth" Subject: Boom! Whoosh...... Newsgroups: sci.space In article <37860@scicom.AlphaCDC.COM> wats@scicom.AlphaCDC.COM (Bruce Watson) writes: >In article <1993May8.230330.19720@ringer.cs.utsa.edu+ sbooth@lonestar.utsa.edu (Simon E. Booth) writes: >+ >+Now, with the talk here about this mile-long space balloon, one thing I'd >+like to know is just how they would manage to pack something that huge into >+the payload shroud of a rocket or into the payload bay of a shuttle? >+And exactly what would it look like from the ground? > >The Echo I balloon launched in 1960 was 100 feet in diameter and fit >uninflated into a 28-inch diameter package and weighed 132 pounds. > >At a distance of 300 kilometers, one mile subtends 0.3 degrees. >The sun and the moon subtend 0.5 degrees. > That's right- I read in later posts that the mylar for the Echo balloons was ultra-thin. But folding a mile-long balloon would still be tricky, although if thin enough it could fit into a payload shroud. about the size of the moon from the ground, it might look larger on the horizon, like the full moon. Of course it would move too fast for that effect to really be noticeable. And in the fall we'll see the harvest Coke can rising on autumn nights. :-) Simon ------------------------------ Date: Mon, 10 May 1993 22:45:12 GMT From: "Simon E. Booth" Subject: Boom! Whoosh...... Newsgroups: sci.space In article <1993May10.134819.8227@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >In article <37860@scicom.AlphaCDC.COM> wats@scicom.AlphaCDC.COM (Bruce Watson) writes: >>In article <1993May8.230330.19720@ringer.cs.utsa.edu+ sbooth@lonestar.utsa.edu (Simon E. Booth) writes: >>+ >>+Now, with the talk here about this mile-long space balloon, one thing I'd >>+like to know is just how they would manage to pack something that huge into >>+the payload shroud of a rocket or into the payload bay of a shuttle? >>+And exactly what would it look like from the ground? >> >>The Echo I balloon launched in 1960 was 100 feet in diameter and fit >>uninflated into a 28-inch diameter package and weighed 132 pounds. > >If the scaling held, we'd be looking at a 123 foot diameter package >weighing 3.5 tons for a 1 mile in diameter Echo style balloon. The >mass is managable, but the payload shroud might be another matter. > >The more serious problem would be finding the hanger for painting >on the logos before launch. Echo was inflated in a blimp hanger, >but a one mile high hanger might be harder to find. :-) > This is exactly what I was thinking. Unless they paint the logos in sections and attach the sections without actually having to inflate it on the ground. Or inflate the whole thing outdoors. Simon ------------------------------ Date: Mon, 10 May 93 20:54:32 BST From: Peter Churchyard Subject: FAQ and Sky hooks.. Newsgroups: sci.bio,sci.space Is there are FAQ for this group. Like whats the feasiblilty of an sky hook, elevator to orbit? Are modern materials orders of magnitude to weak? or is it close? Pete(I'd rather walk). ------------------------------ Date: Mon, 10 May 1993 17:16:39 GMT From: Steve Willner Subject: HST Servicing Mission Newsgroups: sci.space,sci.space.shuttle,sci.astro In article <1993May6.185003.9670@stsci.edu>, wissler@stsci.edu (Steve Wissler,G10,xxx) writes: > However, how much would it cost per year to service this new > telescope, probably $250 million per year Zero. Consider a possibly familiar analogy. A dishwasher costs $500 and can be expected to last 5 years, perhaps longer. If the manufacturer wants to sell you a "service contract" for $125 per year, is that a good deal? In fact, I'm not aware of any future NASA Astrophysics mission planning for servicing. In this respect, as in so many others, "It won't be like HST." has become almost a mantra. -- Steve Willner Phone 617-495-7123 Bitnet: willner@cfa Cambridge, MA 02138 USA Internet: willner@cfa.harvard.edu member, League for Programming Freedom; contact lpf@uunet.uu.net ------------------------------ Date: 10 May 1993 22:04:28 GMT From: Claudio Oliveira Egalon Subject: landing at Edwards vs. the Cape Newsgroups: sci.space >> Space shuttle- more people, more hardware, more trips than any other >> space vehicle. Who can argue with the numbers? > Presumably you are restricting this argument to manned USA space vehicles. > If not, a brief review of AW&ST 's annual summaries of USSR/Russian > launch activity over the last decade might modify the above. I haven't read the annual summaries of AW&ST BUT I DO remember that just after the Challenger accident, Air & Space magazine published a poster entitled "Space Explorers", with the photo of everyone that had flown in space since the beggining of the Space Age, up to that moment. Well, I decided to go through the trouble of counting the heads that flew in an American spacecraft and in the Soviet spacecraft and I found out that more people had flown in an American space ship than in a Soviet one. Since then, with the shuttle back to flight, I guess that this gap has increased even more but, do not forget, we are talking about the number of different individuals, that flew in space... Also, I believe that this is mostly due to the Shuttle since no other spacecraft can carry as many astronauts as the Shuttle does. Please correct me if I am wrong. C.O.Egalon@larc.nasa.gov Claudio Oliveira Egalon ------------------------------ Date: 10 May 1993 20:39 UT From: Ron Baalke Subject: Life on Mars. Newsgroups: sci.space,sci.bio In article , henry@zoo.toronto.edu (Henry Spencer) writes... >The Viking life-detection results are best described as "confusing". There >were some indications for and some against -- while there were positive >results in some tests, the overall pattern was not what would have been >expected from life. The devastating blow was the failure of the GCMS >experiment to find any organic molecules at all in the soil; it would >give positive results even on Antarctic soil, but it came up negative >on Mars. The simplest explanation does seem to be some kind of highly >active surface chemistry. Somewhat unorthodox forms of life remain a >possibility that can't be ruled out. The Viking results showed that there was either some peculiar chemistry on Mars, or there is some peculiar life form unlike anything on Earth, but we don't know which one. I've always thought that the Viking experiments were flawed in that they were looking for Earth-like life in a non-Earth environment (this being my own personal opinion, mind you). The assumption was that if there is life on Mars, then it would be similar to life on Earth. We really don't know if this is a valid assumption. The difficulty in designing an experiment to detect a life form on another planet is acknowledged, but on the same token maybe the experiments should of allowed some leeway for the unexpected. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Once a year, go someplace /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you've never been before. |_____|/ |_|/ |_____|/ | ------------------------------ Date: 10 May 1993 20:51 UT From: Ron Baalke Subject: Life on Mars. Newsgroups: sci.space,sci.bio In article <93130.121835RPT378@MAINE.MAINE.EDU>, Larry Zibilske writes... >I dont know that the results have completely excluded the possibility of life >on Mars. I have been trying to find the biodata for the Viking missions to >examine myself. I am a soil microbiolgist and my interests include very low >level microbial activity detection. I see, for instance, very low but definite > metabolic activity in very environmentally extreme conditions (temperature, >moisture) and someone mentioned that the data show a pattern similar to that >seen in the Viking data....but I cant find the Viking data. Does anyone know >where this might be obtained? (not the polished public press stuff; but the >journal article level or orginal pub data)? The Viking results were published the Journal of Geophysical Research, Volume 82, number 28, September 30, 1977. This is a rather large volume with over 700 pages, and ten articles on the biology experiments are included. If you can't find this journal at your library, you can order it the American Geophysical Union who reprinted it under the name "Scientific Results of the Viking Project". You can reach AGU at: AGU, 2000 Florida Avenue, N.W., Washington D.C., 20009. Their phone number is (202) 462-6900. I forget the exact price, but it was at some bargain amount of around $10. Also, there is good layman article on the Viking science results in the January 1977 issue of National Geographic. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Once a year, go someplace /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you've never been before. |_____|/ |_|/ |_____|/ | ------------------------------ Date: 10 May 1993 21:54 UT From: Ron Baalke Subject: Life on Mars. Newsgroups: sci.space,sci.bio In article <1sk847$m67@usenet.INS.CWRU.Edu>, ak104@cleveland.Freenet.Edu (Robert Clark) writes... > > > In the June 1993 issue of _Final Frontier_ there is an interview with >Dr. Gilbert Levin who designed one of the life detection experiments on >the Viking missions. > He's of the opinion that the data from his experiment is indicative of >life on Mars. > >He gives several reasons for this: > > 1.) His experiment was the most sensitive of the detection methods. > > 2.) The three experiments were designed to detect different kinds > of life so it should be expected that his gave the only repeated > life signs. > > 3.) One of the detectors was known to not even be sensitive enough to > detect life even in some Antartica soil samples known to contain life. Of the three Viking biology experiments, only Dr. Levin's experiment yielded data which met the criteria originally developed to determine a positive response for detection of life. If you considered Dr. Levin's Labeled Release experiment, and only his experiment alone, then the conclusion would be that living organisms were detected in the Martian soil. However, if you consider the results from the other Viking experiments, then you cannot readily draw such a conclusion. The Gas Chromatograph Mass Spectrometer did not detect any organic compounds in the Martian soil. This is particularly crucial, because the biologists could not explain how there could be life without a trace of organic compounds, unless Martian life is substantially different from Earth life. The Gas Exchange experiment indicated some kind of super oxide was present which may explain the results in Levin's experiment. I think Dr. Levin is trying to discredit the Viking results which contradict the results from his experiment. > 4.) In some of the images of martian rocks, there are seasonal changes in > their coloring similar to moss growing on terrestrial rocks. I remember seeing Viking images that had color differences that was due to frost, but this is the first I've heard of it being attributed to moss. > Before I read this article I wasn't aware that any of the experiments > gave repeated life signs. Another thing that surprised me was that after > all these years there still hasn't been a symposium convened to discuss > the data returned by the Viking life experiments. The experiments were repeated several times, and the same results were obtained each time. There was a Viking conference in Washinton D.C. in 1986 (Viking's 10th landing anniversary). ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Once a year, go someplace /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you've never been before. |_____|/ |_|/ |_____|/ | ------------------------------ Date: 10 May 1993 17:58:31 -0400 From: Pat Subject: Location Devices for RVs, also SARSATs Newsgroups: sci.space Wales. THe Russian side of the Sarsat system was up years before the american side. I don't remember if we built the flight packages or if it was just a joint co-ordination office. pat ------------------------------ Date: 10 May 1993 23:35 UT From: Ron Baalke Subject: Mars Observer Update - 05/10/93 Newsgroups: sci.space,sci.astro,alt.sci.planetary Forwarded from: PUBLIC INFORMATION OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011 MARS OBSERVER MISSION STATUS May 10, 1993 The Mars Observer spacecraft again switched into contingency mode -- a self-protective default mode -- at about 4:57 a.m. Pacific Daylight Time on Sunday, May 9, 1993. Flight controllers at JPL have decided to evaluate some software modifications that will improve the spacecraft's attitude control performance before returning to the normal outer cruise mode. Contingency mode occurs when the spacecraft is unable to correctly identify its position in space with respect to certain stars and the sun. Specifically, the spacecraft's sun sensor indicates that the position of the sun is not in the same location as its on-board flight software expects it to be. When that happens, the spacecraft thinks it has lost its attitude reference and automatically points at the sun, throwing the high- gain antenna off target with Earth. Communications are automatically switched from the high-gain to the low-gain antenna. All unnecessary power loads, such as the science instruments and tape recorders, are turned off. A software fix that will redefine some attitude control parameters is being evaluated by JPL systems engineers. That software was expected to be ready for uplink in the next several weeks. Today Mars Observer is about 20 million kilometers (12.5 million miles) from Mars and 220 million kilometers (136 million miles) from Earth. The spacecraft is traveling at a velocity of about 7,000 kilometers per hour (4,000 miles per hour) with respect to Mars. ##### ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Once a year, go someplace /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you've never been before. |_____|/ |_|/ |_____|/ | ------------------------------ Date: Mon, 10 May 1993 21:53:11 GMT From: "Phil G. Fraering" Subject: Neil Armstrong's first words (the real ones) Newsgroups: sci.space hqm@ai.mit.edu (Henry Minsky) writes: >Can anyone tell me what Neil Armstrong's real first words were after >he stepped out of the apollo 11 lander? Someone told me that they were >something like "The soil is sandy and loose, I can kick it around with >my toe" or something like that. Actually, it was: "That's one small step for man,... hey, guys, there's this freaking ALIEN on the crater rim!" -- Phil Fraering |"Number one good faith! You convert, pgf@srl02.cacs.usl.edu|you not tortured by demons!" - anon. Mahen missionary ------------------------------ Date: Mon, 10 May 1993 21:13:12 GMT From: Josh Hopkins Subject: Space Advertising Newsgroups: sci.space wats@scicom.AlphaCDC.COM (Bruce Watson) writes: >In article <1993May8.230330.19720@ringer.cs.utsa.edu+ sbooth@lonestar.utsa.edu (Simon E. Booth) writes: >+ >+Now, with the talk here about this mile-long space balloon, one thing I'd >+like to know is just how they would manage to pack something that huge into >+the payload shroud of a rocket or into the payload bay of a shuttle? >+And exactly what would it look like from the ground? >The Echo I balloon launched in 1960 was 100 feet in diameter and fit >uninflated into a 28-inch diameter package and weighed 132 pounds. >At a distance of 300 kilometers, one mile subtends 0.3 degrees. >The sun and the moon subtend 0.5 degrees. And that's going to define what type of advertising can be done. Puting up a bright point (or collection of them) isn't hard and would attract attention. However, it's going to be very hard to put your logo in space, simply because space is a rather big place. If a one mile billboard at 300 km subtends .3 degrees, and a human can resolve 1 arcminute (I'm pulling that from memory - please correct me if I'm wrong) then a 1 mi^2 billboard has something like 20x20 pixels. You might be able to draw golden arches legibly, but certainly not the Coke logo. I recall being at the top of a peak in the French Alps where the horizon was something like 80 km away. Even other mountains start to look very small very fast at these kinds of distances. -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu "Find a way or make one." -attributed to Hannibal ------------------------------ Date: 10 May 93 19:06:09 -0600 From: Bill Higgins-- Beam Jockey Subject: Space Advertising and Visual Acuity Newsgroups: sci.space In article , jbh55289@uxa.cso.uiuc.edu (Josh Hopkins) writes: > wats@scicom.AlphaCDC.COM (Bruce Watson) writes: >>At a distance of 300 kilometers, one mile subtends 0.3 degrees. >>The sun and the moon subtend 0.5 degrees. > > And that's going to define what type of advertising can be done. Puting up a > bright point (or collection of them) isn't hard and would attract attention. > However, it's going to be very hard to put your logo in space, simply because > space is a rather big place. If a one mile billboard at 300 km subtends .3 > degrees, and a human can resolve 1 arcminute (I'm pulling that from memory - > please correct me if I'm wrong) then a 1 mi^2 billboard has something like > 20x20 pixels. You might be able to draw golden arches legibly, but certainly > not the Coke logo. A quick look at the usual bible of this, *Human Factors Engineering* by Ernest J. McCormick suggests that you're in the right ballpark. Visual acuity (angular resolution) depends on the contrast of what you're looking at, and on the amount of illumination available. If your orbiting billboard has something very bright against the black of space, you might be able to get down to 0.7 or 0.5 arcmin. The Moon is a rotten case because it's so dark; maria have an albedo of 7% to 10%, highlands a bit higher (11%-18%). So dropping or painting absolutely black stuff on the Moon would never get you a contrast better than about 15%, which limits acuity to about 1 arcmin-- call it 30 pixels across the lunar equator. (This is also bad news for those of you who are working out laser-drawn cartoons to illuminate the Moon.) You could do better by spraying high-albedo stuff-- maybe iron or aluminum dust?-- if it was 85% albedo, you could get about 82% contrast, and get about 60 pixels under good illumination conditions (full Moon, I guess). Lots of people on Earth have binoculars or telescopes. Maybe you should put the Golden Arches on the Moon, then write the name "McDonald's" for the benefit of readers with optical aids. In really small letters (like 1 km high) we could write "IF YOU CAN READ THIS, THANK AN ASTRONOMER." How long before there are customers on the Moon and people think about drawing designs on the Earth for their viewing pleasure? Bill Higgins, Beam Jockey | Here Lies Bill Higgins: Fermi National Accelerator Laboratory | He Never Ever Learned Bitnet: HIGGINS@FNAL.BITNET | To Play Guitar So Well Internet: HIGGINS@FNAL.FNAL.GOV | But He Could Read and Write SPAN/Hepnet: 43011::HIGGINS | Just Like Ringing A Bell ------------------------------ Date: Mon, 10 May 1993 21:29:04 GMT From: kjenks@gothamcity.jsc.nasa.gov Subject: Vandalizing the sky Newsgroups: sci.space Ken Arromdee (arromdee@jyusenkyou.cs.jhu.edu) wrote: : But this would require far more of my time and resources to do than walking : past an earthly billboard. Even if we have commercial space travel, it's as : if whenever I wanted to see past an Earthly billboard, I had to take a trip : to Alaska. In the US, if you want to find a place which is not affected by the Hand of Man, you DO have to go to Alaska. Most of the country has been altered, in one way or another, by human presence. No place on Earth is entirely untouched by human intervention. We humans are part of nature, and you'll find us and our influence everwhere you look. One of the most visible examples is light pollution around cities, and changes in the atmosphere everywhere on the planet. (You have heard about that little problem with the ozone layer, I presume.) Whining that "My view of the sky will be messed up!" not a valid argument against space-based advertising. Try another. (I can think of several.) -- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office kjenks@gothamcity.jsc.nasa.gov (713) 483-4368 "NASA turns dreams into realities and makes science fiction into fact" -- Daniel S. Goldin, NASA Administrator ------------------------------ Date: Mon, 10 May 1993 21:51:11 GMT From: kjenks@gothamcity.jsc.nasa.gov Subject: Vandalizing the Sky Newsgroups: sci.space F.Baube[tm] (flb@flb.optiplan.fi) wrote: [...] : That's roughly akin to saying let's let Anaconda strip-mine : the Grand Canyon so that strip-mining can boldly go where no : strip mining technology has gone before .. because after all, : mining means profits, and profits mean technological advance- : ment, and technogical advancement means prosperity, and pros- : perity means happiness, and so to hell with the Grand Canyon .. Space advertisement in LOW Earth Orbit is very short term -- on the order of a few years before the orbit decays. (Higher orbits last longer.) Advertisers will certainly be aware of the environmental aspects of their advertising. Fred's argument is roughly akin to saying that it's bad to cut down trees, so we shouldn't advertise in newspapers. Think that through, Fred. Picture this: Our space billboard is a LARGE inflatable structure, filled with "bio-degradable" foam instead of gas. It scoops up space debris as it orbits, thus CLEANING the space environment and bringing you The Pause That Refreshes at the same time. Because of the large drag coefficient, it will de-orbit -- safely burning up -- within a year. Embedded in the foam structure is a small re-entry vehicle, which does not burn up during entry. It contains the electronics and propulsion system (which may be refurbished and re-used) as well as space science experiments proposed and built by high school students in advertiser-sponsored science fairs. Advertisers buy time on the billboard, whose surface is made up of tiny mirrors controlled by the avionics package. The avionics can reconfigure the mirrors to reflect different messages at different parts of the globe. Clever programming allows different languages to every country. During orbital night, the mirrors turn perpendicular to the surface, and small lights are revealed. The lights spell out messages for all to see. -- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office kjenks@gothamcity.jsc.nasa.gov (713) 483-4368 "HERE MEN FROM THE PLANET EARTH FIRST SET FOOT UPON THE MOON JULY 1969, A.D. WE CAME IN PEACE FOR ALL MANKIND." ------------------------------ Date: Tue, 11 May 1993 10:25:46 +0100 From: zcapk43@ucl.ac.uk (Peter Newman) In an article on 1993 May 9, James Nicholl writes: >Is a 550+ AU observatory (Unmanned, of course) something I might expect to see... James: Check out the book "Space: The Next 100 Years" by Nicholas Booth (1990, Mitchell Beazley, London, ISBN: 0-85533-791-5) regarding the TAU (Thousand Astronomical Unit) mission proposed (apparently) by JPL. Would use ion thrusters to move about 20 AU/year, so would reach 500 AU in your life time (god willing). Don't know the current status, so maybe someone from JPL could pick up the thread... Bon voyage, Pete Newman Astronomy I, Dept. of Physics & Astronomy University College London England, WC1E 6BT ------------------------------ End of Space Digest Volume 16 : Issue 554 ------------------------------